Police in Belgium on Wednesday were holding seven people for questioning after raids in the Brussels region as part of an ongoing counter-terrorism operation, prosecutors said.
The searches of eight houses were linked to returning jihadi fighters from Syria and separate from investigations into ISIS attacks in Paris in November 2015 and the bombings in Brussels on March 22 last year, a statement said.
“No weapons or explosives were found. In all, seven persons were arrested and taken for questioning,” it said.
Belgium is the EU country with the highest per capita number of fighters who have traveled to Syria and Iraq, a figure estimated at 465.
The authorities have tried for years to clamp down on their recruitment, fearing they will return home battle-hardened and even more dangerous.
Meanwhile, several sources told Agence France Presse that ISIS suicide bombers who attacked Brussels airport last year targeted passengers travelling to the United States and also Jewish people.
The Belgian-led investigation believes a check-in counter for an American carrier was one of the targets in the attacks, the sources said on condition of anonymity.
They also suspect that travelers to Israel may have been in the crosshairs, and that airport security camera footage shows one bomber apparently pursuing Hasidic Jews seconds before one of the blasts.
ISIS bombers Najim Laachraoui and Ibrahim El Bakraoui killed 16 people at Zaventem airport. Around an hour later Bakraoui’s brother Khalid attacked a metro station near EU headquarters, killing another 16.
One source close to the investigation told AFP, which contacted investigators in several countries, that one of the airport bombers “attacked the Delta Airlines check-in”.
“We know they wanted to target Americans,” said the source, who asked not to be named. “It’s clear they had quite specific targets.”
Asked if these targets included the check-in counter for a flight to Israel, he replied: “We know they were obsessed with the Israelis too.”
Belgium has been on high alert since the Paris and Brussels attacks, with investigators believing they were planned and carried out by the same ISIS cell based in the Belgian capital.